Diversity of Planktonic Fauna of the Pechora River Delta

Abstract

The structure and diversity of zooplankton of the mouth of the largest river in the European North, the Pechora, is studied. The river delta, an adjacent piece of the Pechora course, the estuary (Korovinskaya Bay), and lakes on its northern coast—in Timan Tundra—are in the studied region. In the delta of the Pechora River, the planktonic fauna is rich and unique in structure, in which rotifers (105 species) and cladocerans (55 species) prevailed; thermophilic invertebrates are present in zooplankton, but psychrophilic ones are revealed. Among copepods, brackish taxa and also a possible recent invader of the region (Eurytemora sp.) are found. The analysis of alpha and beta diversities of planktonic communities of the studied region shows the highest indexes for the delta water bodies relative to others and for the lake zooplankton in general. In our opinion, such diversity is due to a variety of environmental conditions and also features of gradients of the dominating environmental factors: temperature, anthropogenic, etc.